Effect of gender on ocular vestibular-evoked myogenic potentials via various stimulation modes.

OBJECTIVE: This study compared the characteristic parameters of ocular vestibular-evoked myogenic potentials (oVEMPs) via air-conducted sound (ACS), bone-conducted vibration (BCV), and galvanic vestibular stimulation (GVS) modes between male and female adults to determine whether gender affects oVEMPs.

METHODS: Twenty healthy volunteers, 10 males (age, 24-33 years) and 10 females (age, 24-33 years), underwent oVEMP tests using ACS, BCV and GVS modes.

RESULTS: No significant differences existed in the mean nI latency, pI latency and nI-pI interval between the males and females. However, the mean oVEMP amplitude in males was significantly larger than that of females, regardless of whether ACS, BCV or GVS mode was used. In contrast, asymmetry ratio of the amplitude did not show gender difference. Additionally, the mean body mass index (BMI) was 22.3 ± 1.8 kg/m(2) for male group and 19.6 ± 1.6 kg/m(2) for female group. Significant correlations existed between the BMI and oVEMP amplitude.

CONCLUSIONS: Gender difference exists in oVEMP amplitude, which may be attributed to variance in the muscle bulk between males and females.

SIGNIFICANCE: Ocular VEMPs should be interpreted with the asymmetry ratio rather than raw amplitude itself.